181465 has 4 divisors (see below), whose sum is σ = 217764. Its totient is φ = 145168.

The previous prime is 181459. The next prime is 181499. The reversal of 181465 is 564181.

181465 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 564181 = 241 ⋅2341.

It can be written as a sum of positive squares in 2 ways, for example, as 24649 + 156816 = 157^2 + 396^2 .

It is a cyclic number.

It is not a de Polignac number, because 181465 - 2³ = 181457 is a prime.

It is a Duffinian number.

181465 is a lucky number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18142 + ... + 18151.

It is an arithmetic number, because the mean of its divisors is an integer number (54441).

2¹⁸¹⁴⁶⁵ is an apocalyptic number.

It is an amenable number.

181465 is a deficient number, since it is larger than the sum of its proper divisors (36299).

181465 is an equidigital number, since it uses as much as digits as its factorization.

181465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36298.

The product of its digits is 960, while the sum is 25.

The square root of 181465 is about 425.9870890062. The cubic root of 181465 is about 56.6149277844.

It can be divided in two parts, 181 and 465, that added together give a palindrome (646).

The spelling of 181465 in words is "one hundred eighty-one thousand, four hundred sixty-five".